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Flight Reliability

WN 1399 · Southwest Airlines

This number covered several routes in this period.

One number, several routes.

Airlines reuse flight numbers, and WN 1399 moved between routes during this period. Numbers below combine all of them, so treat them as background, not a verdict. For a cleaner answer, check the route you are actually flying.

Combined across all its routes

77%
Arrive within 15 minutes
4 min
Average arrival delay
1.0%
Cancelled
5 min early
Median arrival delay

Based on 418 historical flights. Data through May 2026.

The breakdown

On-time by weekday
  • Mon73%(64 flights)
  • Tue87%(53 flights)
  • Wed96%(52 flights)
  • Thu61%(67 flights)
  • Fri70%(64 flights)
  • Sat82%(49 flights)
  • Sun77%(65 flights)
On-time by departure window
  • 6–9 AM92%(75 flights)
  • 9 AM–12 PM89%(56 flights)
  • 12–3 PM87%(39 flights)
  • 3–6 PM61%(127 flights)
  • 6–9 PM77%(88 flights)
  • 9 PM–12 AM72%(29 flights)
On-time trend by month
73%
May

Jun 63% → May 73% on time

On-time arrival percentage by month
MonthOn-time percentageFlights
June 202563%40
July 202551%43
August 202583%36
September 202591%34
October 202584%32
November 202572%32
December 202581%31
January 202685%40
February 202677%47
March 202693%28
April 202684%25
May 202673%26
Departures on time
73%
Diverted
0%
Flights flown
414
Months covered
12

Keep nerding

Based on 418 historical flights, because apparently we checked. Historical flight data: U.S. Bureau of Transportation Statistics, June 2025 – May 2026. Data through May 2026. How we calculate this.